In a wireless network, for example, a cellular network, data is transmitted from a Base Station (BS) to a subscriber device or vice versa. A multi-carrier system of the wireless network employs multiple subcarriers in each carrier channel of the network. Examples of multi-carrier systems include, but are not limited to, Orthogonal Frequency Division Multiplexed (OFDM) systems, Orthogonal Frequency Division Multiple Access (OFDMA) systems, and the like.
Subcarriers are allocated to subscriber devices for data transmission. Several methods are available for allocating subcarriers to subscriber devices. One of the known methods employs OFDMA for subcarrier allocation or selection. The method includes partitioning subcarriers into groups of clusters of subcarriers. When an indication of a selection by the subscriber of one or more groups is received, clusters in the groups are allocated, for use in the communication with the subscriber.
However, there are several design/engineering problems associated with the allocation of subcarriers to subscriber devices. This is because the data to be transmitted or received has certain Quality of Service (QoS) requirements, such as delay and throughput requirements. For example, voice data may have a small throughput requirement but stringent delay requirements. Further, data such as streaming video, Internet downloads, and file transfers have requirements that can vary at every instance of the transmission. Further, the base station (BS) and the subscriber device may have constraints such as transmit and receive power constraints. Moreover, carrier channel conditions may vary both across sub-carriers and subscriber devices. Therefore, it is difficult to satisfy the QoS requirements, given the carrier channel conditions and constraints.
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